1. Field of the Invention
This invention relates to an electron microscope such as a scanning electron microscope, a transmission electron microscope, etc., a method for operating the electron microscope, and a computer-readable medium.
2. Description of the Related Art
Nowadays, an electron microscope using an electron lens as well as an optical microscope using an optical lens and a digital microscope is used as an enlargement observation apparatus for enlarging a microbody. The electron microscope is provided by electronically optically designing an image formation system such as an optical microscope as the travel direction of electrons is refracted freely. The available electron microscopes include a transmission electron microscope, a reflection electron microscope, a scanning electron microscope, a surface emission electron microscope (field-ion microscope), and the like. The transmission electron microscope uses an electron lens to form an image of electrons passing through, a specimen, a sample, etc. The reflection electron microscope forms an image of electrons reflected on the surface of a specimen. The scanning electron microscope scans a convergent electron beam over the surface of a specimen and uses secondary electrons from the scanning points to form an image. The surface emission electron microscope (field-ion microscope) forms an image of electrons emitted from a specimen by heating or ion application.
The scanning electron microscope (SEM) is an apparatus for using a secondary electron detector, a reflection electron detector, etc., to take out secondary electrons, reflection electrons, etc., occurring upon application of a thin electron beam (electron probe) to an objective specimen and displaying an image on a display screen of a CRT, LCD, etc., for the operator mainly to observe the surface form of the specimen. On the other hand, the transmission electron microscope (TEM) is an apparatus for allowing an electron beam to pass through a thin-film specimen and providing electrons scattered and diffracted by atoms in the specimen at the time as an electron diffraction pattern or a transmission electron-microscopic image, thereby enabling the operator mainly to observe the internal structure of a substance.
When an electron beam is applied to a solid specimen, it passes through the solid by energy of the electrons. At the time, an elastic collision, elastic scattering, and inelastic scattering involving an energy loss are caused by the interaction between the nucleuses and the electrons making up the specimen. As inelastic scattering occurs, the intra-shell electrons of the specimen elements and X-rays, etc., are excited, and secondary electrons are emitted, the energy corresponding thereto is lost. The emission amount of the secondary electrons varies depending on the collision angle. On the other hand, reflection electrons scattered backward by elastic scattering and emitted again from the specimen are emitted in the amount peculiar to the atom number. The scanning electron microscope uses the secondary electrons and the reflection electrons. The scanning electron microscope applies electrons to a specimen and detects the emitted secondary electrons and reflection electrons for forming an observation image.
However, the electron microscope such as SEM or TEM involves a problem of difficult operation as compared with enlargement observation apparatus such as an optical microscope and a digital microscope. Particularly, it takes time until an observation image is actually provided in addition to a large number of setup items of image observation conditions to pick up an observation image. Thus, what observation image screen is provided in response to the specified image observation condition cannot be checked in real time, and it is difficult to understand how one setup condition is reflected on the observation image screen. Particularly, a beginner unfamiliar with operation of an electron microscope cannot forecast how which item of the observation conditions will affect an image, and thus will search for an observation image by trial and error while changing the image observation conditions in various manners. Thus, it is hard for the beginner to operate an electron microscope and often an expert operator operates an electron microscope.
The expert operator can forecast the general effect of each item of the observation conditions on an observation image to some extent. However, in actual image observation, the effect changes depending on the condition and thus in the end, it becomes necessary to actually obtain an observation image and check the image and a search is made for the optimum condition by trial and error. Therefore, the expert operator also has a desire to use an easily operable electron microscope for enabling the operator to easily check how an observation image changes under various image observation conditions.
It is therefore an object of the invention to provide an electron microscope provided with a guidance function to facilitate setting the electron microscope, a method for operating n electron microscope, and a computer-readable medium.
In order to accomplish the object above, the following means are adopted. According to a first aspect of the present invention, there is provided an electron microscope for picking up an observation image of a specimen based on an image observation condition, the electron microscope comprising:
an image observation condition setting section for setting a plurality of different image observation conditions for a predetermined observation image picked up under a predetermined image observation condition;
an observation image acquisition section for picking up a plurality of observation images based on the plurality of image observation conditions set through the image observation condition setting section;
a second display section for simultaneously displaying the plurality of observation images picked up by the observation image acquisition section;
an observation image selection section for selecting a desired observation image from among the observation images displayed on the second display section; and
a first display section for displaying on an enlarged scale the observation image selected through the observation image selection section.
The electron microscope according to a second aspect of the present invention is characterized by the fact that the image observation condition setting section automatically sets a plurality of acceleration voltage conditions with at least an acceleration voltage changed as the different image observation conditions in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a third aspect of the present invention is characterized by the fact that the image observation condition setting section automatically makes a detector selection as the different image observation conditions in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a fourth aspect of the present invention is characterized by the fact that the observation images displayed on the second display section include a plurality of secondary electron images in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a fifth aspect of the present invention is characterized by the fact that the observation images displayed on the second display section include a plurality of reflection electron images in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a sixth aspect of the present invention is characterized by the fact the observation images displayed on the second display section include at least one secondary electron image and at least one reflection electron image in addition to the characteristic according to the first aspect of the present invention.
Further, the observation images displayed on the second display section may be made up of a plurality of secondary electron images and at least one reflection electron image.
The electron microscope according to a seventh aspect of the present invention is characterized by the fact that the observation image acquisition section picks up the observation images in the ascending order of the acceleration voltages in addition to the characteristic according to the second aspect of the present invention.
The electron microscope according to a eighth aspect of the present invention is characterized by the fact that the observation images acquisition section picks up the observation images in the order as each secondary electron image is picked up and then each reflection electron image is picked up in addition to the characteristic according to the sixth aspect of the present invention.
The electron microscope according to a ninth aspect of the present invention is characterized by the fact that it further comprises an adjustment section for adjusting the observation image selected through the observation image selection section with respect to at least any of focus, brightness, or contrast in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a tenth aspect of the present invention is characterized by the fact that it further comprises a retention section for retaining the image observation conditions corresponding to the observation images displayed on the second display section in addition to the characteristic according to the first aspect of the present invention.
The electron microscope according to a eleventh aspect of the present invention is characterized by the fact that the image observation condition setting section calls the retained image observation conditions from the retention section to set the different image observation conditions, and the image observation acquisition section picks up a plurality of observation images based on the called image observation conditions in addition to the characteristic according to the tenth aspect of the present invention.
The electron microscope according to a twelfth aspect of the present invention is characterized by the fact that the image observation condition setting section sets a plurality of new image observation conditions based on the image observation condition of the observation image selected by the observation image selection section, and the image observation acquisition section picks up a plurality of observation images based on the setup new image observation conditions in addition to the characteristic according to the first aspect of the present invention.
For example, a plurality of new image observation conditions are set with the acceleration voltage changed based on the acceleration voltage of the selected observation image with the value as the center.
Further, in order to accomplish the object above, according to a thirteenth aspect of the present invention, there is provided a method for operating an electron microscope which picks up an observation image of a specimen based on an image observation condition, the method comprising:
setting a plurality of different image observation conditions for a predetermined observation image picked up under a predetermined image observation condition;
picking up a plurality of observation images based on the setup image observation conditions;
simultaneously displaying the plurality of picked-up observation images on a second display section;
selecting a desired observation image from among the observation images displayed on the second display section; and
displaying the selected observation image on a first display section on an enlarged scale.
The electron microscope operation method according to a fourteenth aspect of the present invention is characterized by the fact that it further comprises manually setting at least a spot size of an electron beam on the specimen, an acceleration voltage, a detector type, a specimen position, and an observation magnification as the predetermined image observation condition, and picking up an observation image based on the setup image observation condition as the predetermined observation image, wherein the plurality of different image observation conditions are automatically set based on the predetermined observation image in addition to the characteristic according to the thirteenth aspect of the present invention.
According to a fifteenth aspect of the present invention, there is provided a method for operating an electron microscope which picks up an observation image of a specimen based on an image observation condition, the method comprising:
setting a plurality of different image observation conditions for a predetermined observation image picked up under a predetermined image observation condition;
simply picking up a plurality of observation images based on the setup image observation conditions;
simultaneously displaying the plurality of picked-up simple observation images on a second display section;
selecting a desired simple observation image from among the simple observation images displayed on the second display section; and
performing an usual image picking-up based on the image observation condition corresponding to the selected simple observation image.
The simple image picking up is as follows: To acquire an observation image under the optimum image observation condition, one or more preliminary image observation conditions are set before usual image picking up is performed, and one or more simple observation images are picked up based on the one or more image observation conditions.
According to a sixteenth aspect of the present invention, there is provided a method for operating an electron microscope which picks up an observation image of a specimen based on an image observation condition, the method comprising:
specifying at least characteristics of a specimen as setup items of a predetermined image observation condition;
setting the predetermined image observation condition based the specified characteristics of the specimen;
simply picking up an observation image under the predetermined image observation condition and displaying the picked-up simple observation image on a first display section,
setting one or more simple image observation conditions with at least an acceleration voltage or a detector changed for the simple observation image displayed on the first display section displaying one or more simple observation images simply picked up based on the one or more simple image observation conditions on a second display section;
selecting a desired simple observation image from among the one or more simple observation images displayed on the second display section; and
performing a usual image picking-up based on the simple image observation condition corresponding to the selected simple observation image and displaying the picked-up image on the first display section.
The electron microscope operation method according to a seventeenth aspect of the present invention is characterized by the fact that it further comprises making at least magnification adjustment and position adjustment to the simple observation image displayed on the first display section, before setting the one or more simple image observation conditions, wherein the one or more simple image observation conditions are set for the simple observation image adjusted in at least magnification and position in addition to the characteristic according to the sixteenth aspect of the present invention. Alternatively, it may further comprises making at least magnification adjustment and position adjustment to the selected simple observation image, before performing the usual image picking-up, wherein the usual image picking-up is performed based on the simple image observation condition corresponding to the selected simple observation image at adjusted magnification and position.
According to a eighteenth aspect of the present invention, there is provided a method for operating an electron microscope which picks up an observation image of a specimen based on an image observation condition, the method comprising:
manually setting at least a spot size of an electron beam on the specimen, an acceleration voltage, a detector type, a specimen position, and an observation magnification as setup items of a predetermined image observation condition;
picking up an observation image under the predetermined image observation condition and displaying the picked-up observation image on a first display section;
making at least magnification adjustment and position adjustment to the observation image displayed on the first display section;
setting one or more simple image observation conditions with at least the acceleration voltage or the detector changed for the observation image displayed on the first display section and adjusted in at least magnification and position;
displaying one or more simple observation images simply picked up based on the one or more simple image observation conditions on a second display section;
selecting a desired simple observation image from among the one or more simple observation images displayed on the second display section; and
performing an usual image picking-up based on the simple image observation condition corresponding to the selected simple observation-image and displaying the picked-up image on the first display section.
The electron microscope operation method according to a nineteenth aspect of the present intervention is characterized by the fact that it further comprises setting one or more simple image observation conditions with at least the acceleration voltage or the detector changed as new image observation condition for the selected simple observation image after selecting any desired simple observation image from among the one or more simple observation images displayed on the second display section; displaying one or more simple observation images simply picked up based on the one or more simple image observation conditions on the second display section; selecting a desired simple observation image from among the one or more simple observation images displayed on the second display section; and displaying the selected simple observation image on the first display section in addition to the characteristic according to any of the fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twentieth aspect of the present invention is characterized by the fact that the image observation conditions are preset image observation conditions in addition to the characteristic according to any of the fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twenty-first aspect of the present invention is characterized by the fact that it further comprises printing data of the picked-up observation image; and retaining the data of the observation image in addition to the characteristic according to any of the thirteenth, fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twenty-second aspect of the present invention is characterized by the fact that it further comprises the steps of setting one or more simple image observation conditions with at least the acceleration voltage or the detector changed as new image observation condition for the selected observation image; displaying one or more simple observation images simply picked up based on the one or more simple image observation conditions on the second display section; selecting any desired simple observation image from among the one or more simple observation images displayed on the second display section; and displaying the selected simple observation image on the first display section before the printing step in addition to the characteristic according to the twenty-first aspect of the present invention.
The electron microscope operation method according to a twenty-third aspect of the present invention is characterized by the fact that the simple observation images displayed on the second display section include one or more secondary electron images or one or more reflection electron images in addition to the characteristic according to any of the thirteenth, fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twenty-fourth aspect of the present invention is characterized by the fact that it further comprises the step of retaining a history of the image observation conditions, wherein the history is called as required and any desired image observation condition is selected out of the history, whereby image picking up or simple image picking up can be performed under the same image observation condition as the selected image observation condition in addition to the characteristic according to any of thirteenth, fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twenty-fifth aspect of the present invention is characterized by the fact that it further comprises the step of retaining an image observation condition as required, wherein the retained image observation condition is called as required and image picking up or simple image picking up can be performed under the same image observation condition as the retained image observation condition in addition to the characteristic according to any of the thirteenth, fifteenth, sixteenth and eighteenth aspects of the present invention.
The electron microscope operation method according to a twenty-sixth aspect of the present invention is characterized by the fact that a plurality of image observation conditions are selected from among the retained image observation conditions and based on the selected image observation conditions, a plurality of observation images are simply picked up and can be displayed on the second display section in addition to the characteristic according to the twenty-fourth or twenty-fifth aspect of the present invention.
According to a twenty-seventh aspect of the present invention, there is provided a computer-readable medium including a program executable on a computer for operating an electron microscope which picks up an observation image of a specimen based on an image observation condition, the program comprising instructions having:
a first function of automatically setting a plurality of acceleration voltage conditions with at least an acceleration voltage changed and making a detector selection as different image observation conditions for an observation image picked up under a predetermined image observation condition;
a second function of simply picking up a plurality of observation images in the ascending order of acceleration voltages based on the image observation conditions set through the first function;
a third function of simultaneously displaying on a reduced scale the plurality of simple observation images including at least one secondary electron image and at least one reflection electron image simply picked up through the second function on a second display section;
a fourth function of selecting a desired simple observation image from among the simple observation images displayed on the second display section;
a fifth function of displaying on an enlarged scale the simple observation image selected through the third function on a first display section;
a sixth function of adjusting the observation image displayed on the first display section with respect to at least any of focus, brightness, or contrast;
a seventh function of performing an usual image picking-up based on the image observation condition corresponding to the simple observation image selected and adjusted as required; and
an eight function of retaining a desired image observation condition corresponding to the usually picked-up observation image though the seventh function.
The medium includes a magnetic disk, an optical disk, a magneto-optical disk, semiconductor memory, or any other medium capable of storing a program, such as CD-ROM, CD-R, CD-RW, flexible disk, magnetic tape, MO, DVD-ROM, DVD-RAM, DVD-R, DVD-RW, OR DVD+RW.